A problem that is encountered with the mounting of semiconductor IC chips or dice into packages and onto hybrid microcircuits is subjecting the entire package and other components (e.g., capacitors) to excessive heat. The common, prior art, methods of attaching IC chips to packages and substrates are eutectic die bond, eutectic perform reflow and polymer die bonding. All of these techniques require heat that elevates the package/substrate temperature. The eutectic and eutectic preform reflow die bonds are performed at about 400.degree. C. The epoxy cure temperatures are upwards of 200.degree. C. Because of these high temperature exposures, it is usually necessary to attach an IC die on a substrate before adding other chips and/or discrete components, or mounting the substrates into packages. At the least, this approach is inefficient.
To remove a defective integrated circuit chip from a package/substrate it has been necessary heretofore to, once again, subject the entire package/substrate to a high temperature to melt the bond holding the defective chip in place. This has the disadvantageous tendency to melt the eutectic solder (or destroy the epoxy) bonding other IC chips to the same substrate. Moreover, various other circuit components (e.g., capacitors, chip resistors) mounted on the reheated substrate and even the substrate bond-to-package, can be deleteriously effected by this reheating operation.
The above-discussed problems can be overcome by carrying out integrated circuit chip bonding/removal in accordance with the principles of the present invention.